The present invention relates to an actuator and in particular to an actuator for operating a relatively minute device such as a catheter, a manipulator for operating the cell or a manipulator for operating a robot to be used in a narrow space.
An actuator of the kind which is disclosed in the foregoing application includes a main body having an inner space in the form of a blind bore with an opening, a thin film member connected to the main body for closing the inner space, an amount of thermally expansive gas filled in the inner space, a substance for converting the light into the heat which is accommodated in the inner space, and a controller having a device for guiding the light into the inner space.
In the foregoing actuator, upon application of the light into the inner space of the main body, heat at a degree is generated, and the resultant heat brings the gas into expansion. Thus, the thin film is deformed and the resultant deformation is set to be used as a force for driving a specific element.
However, since the thin film member is less than 1.mu. in thickness, if an unexpected external force is applied during construction or usage of the actuator, the thin film may be broken in the worst case.